<template>
  <div id="home">
    <nav-bar class="home-nav"><div slot="center">购物街</div></nav-bar>
    <tab-control  
        @tabClick="tabClick"
        :titles="['流行','新款','精选']"
        ref="tabControl1"
        class="tab-control"
        v-show="isTabFixed"/>
    <scroll 
      class="content" 
      ref="scroll"
      :probe-type="3"
      @scroll="centscrool"
      :pull-up-load="true"
      @pullingUp = "loadMore">
      <home-swiper :banners="banners"
        @swiperImageLoad="swiperImageLoad"/>
      <recommend-view :recommends="recommends"/>
      <feature-view/>
      <tab-control  
        @tabClick="tabClick"
        :titles="['流行','新款','精选']"
        ref="tabControl2"/>
      <goods-list :goods="showGoods"/>
    </scroll>
    <back-top 
    class="back-top" 
    @click.native="backClick"
    v-show="isShowBackTop"/>
  </div>
</template>

<script>
  import HomeSwiper from './childComps/HomeSwiper'
  import RecommendView from './childComps/RecommendView'
  import FeatureView from './childComps/FeatureView'

  import NavBar from 'components/common/navbar/NavBar'
  import Scroll from 'components/common/scroll/Scroll'
  import TabControl from 'components/content/tabControl/TabControl'
  import GoodsList from 'components/content/goods/GoodsList'
  import BackTop from 'components/content/backTop/BackTop'

  import {getHomeMultidata} from "network/home";
  import {getHomeGoods} from "network/home";
  import {debounce} from "common/utils";
  

  export default {
    name: "Home",
    components: {
      HomeSwiper,
      RecommendView,
      FeatureView,
      NavBar,
      TabControl,
      GoodsList,
      BackTop,
      Scroll
    },
    data() {
      return {
        banners: [],
        recommends: [],
        goods:{
          'pop': {page: 0, list: []},
          'new': {page: 0, list: []},
          'sell': {page: 0, list: []},
        },
        currentType: 'pop',
        isShowBackTop:false,
        isTabFixed: false,
        tabOffsetTop:0,
        saveY:0,
        itemImgListener:null
      }
    },
    computed:{
      showGoods(){
        return this.goods[this.currentType].list
      }
    },
      created() {
      // 1.请求多个数据
      this.getHomeMultidata()
      //2.请求商品数据
      this.getHomeGoods('pop')
      this.getHomeGoods('new')
      this.getHomeGoods('sell')
      
      
    },
      mounted() {
      // 1.图片加载完成的事件监听
      const refresh = debounce(this.$refs.scroll.refresh, 50)

      this.$bus.$on('itemImageLoad', () => {
        refresh()
      })
      
      
    },
      activated(){
        this.$refs.scroll.refresh()
        this.$refs.scroll.scrollTo(0, this.saveY, 0)
        // console.log(this.saveY);
    },
      deactivated(){
        this.saveY = this.$refs.scroll.getCurrentY()
        // console.log(this.saveY);
        this.$bus.$off('itemImgLoad',this.itemImgListener)
        
    },
    methods:{
      //事件监听相关方法
      tabClick(index){
        // console.log(index);
        switch (index) {
         case 0:
            this.currentType = 'pop'
            break
          case 1:
            this.currentType = 'new'
            break
          case 2:
            this.currentType = 'sell'
            break
        }
        this.$refs.tabControl1.curentIndex = index;
        this.$refs.tabControl2.curentIndex = index;
      },
      //返回顶部
      backClick(){
        this.$refs.scroll.scrollTo(0,0);
      },
      //返回顶部按钮的显示与隐藏
      centscrool(position){
        this.isShowBackTop = -position.y > 1000

        //决定tabControl是否吸顶
        this.isTabFixed = (-position.y) > this.tabOffsetTop
      },
      //上拉加载更多
      loadMore(){
        // console.log("genduo");
        this.getHomeGoods(this.currentType)      
        // this.$refs.scroll.scroll.refresh()
      },
      swiperImageLoad(){
        //2.获取tabControl 的 offsettop
        // console.log(this.$refs.tabControl.$el.offsetTop);
        this.tabOffsetTop = this.$refs.tabControl2.$el.offsetTop
        

      },
      //网络请求相关方法
      getHomeMultidata(){
        getHomeMultidata().then(res => {
        // this.result = res;
          this.banners = res.data.banner.list;
          this.recommends = res.data.recommend.list;
        })
      },
      getHomeGoods(type) {
        const page = this.goods[type].page + 1
        getHomeGoods(type, page).then(res => {
          this.goods[type].list.push(...res.data.list)
          this.goods[type].page += 1
          // console.log(res);
          

          // 完成上拉加载更多
          this.$refs.scroll.finishPullUp()
        })
      }
    },
  }
</script>

<style scoped>
  #home{
    /* padding-top: 44px; */
    height: 100vh;
    position: relative;
  }

  .home-nav {
    background-color: var(--color-tint);
    color: #fff;

    /* position: fixed;
    left: 0;
    right: 0;
    top: 0;
    z-index: 9; */
  }

  .content{
    /* height: 300px; */
    overflow: hidden;
    position: absolute;
    top: 44px;
    bottom: 49px;
    left: 0;
  }

  .tab-control{
    position: relative;
    z-index: 9;
  }
</style>
